1. Field of the Invention
The present invention relates to a magnetic recording medium suitable as a recording medium for a hard disc device.
2. Discussion of Background
In recent years, magnetic recording media have been developed for high density recording. As one of methods for reducing media noises, JP-A-63-146219 or IEEE TRANSACTIONS ON MAGNETICS, 26(5), 2700–2750(1990) discloses that a magnetic recording film is made to have a multilayer structure comprising a plurality of magnetic layers and an interlayer interposed between the adjacent magnetic layers to reduce the magnetic interaction between the adjacent magnetic layers. Further, as a means to obtain a high coercive force for high recording density, it has been reported to employ, as an underlayer, NiAl having B2 crystal structure (IEEE TRANSACTIONS ON MAGNETICS, 30 (6), 3951–3953 (1994). EP0704839A1).
In said JP-A-63-146219, in order to reduce noises, an Al2O3, SiO2 or Cr film has been studied as the interlayer to be used for a magnetic recording medium having the above-mentioned magnetic recording film having a multilayer structure, but reduction of noises is still inadequate for an application in future wherein a GMR head will be used. In said EP0704839A1, NiAl has been studied as the underlayer, but no study has been made to let the magnetic recording film have a multilayer structure comprising a plurality of magnetic layers and an interlayer interposed between the adjacent magnetic layers to reduce the magnetic interaction.